tune bench examples: add -pic
minor MoreHashes+C improvements

use strict, no types.
File::Basename only when needed
CMPH.xs: fix ASAN off-by-1 heap overflow, add DESTROY

do not leak cmph_t mphf
also error on empty cmph_packed_size
save_c: add key sizes to hanov-based hashes for ASAN

address-sanitizer complains about out-of-bounds accesses to short keys, when
doing the final memcmp. So we store now the sizes as Ks also, as we do not know
which CFLAGS will be used.
This is also needed for -nul/binary keys.